Electrical distilling apparatus.



c. H. FULTON. ELECTRICAL DISTILLING APPARATUS.

APPLICATION FILED DEC.7. |916.

C. H. FULTON.

ELECTRICAL DISTILLING APPARATUS. APPLICATION FILED DECJ. I9I6.

1,242,337. Patented oct. 9, 1917.

, 3 SHEETS-SHEET 2.

C. H. FULTON.

ELECTRICAL msTlLuNG APPARATUS.

APPLICATION FILED DEC.7. 19H5.

Patented Oct. 9,1917.

43 SHEETS-SHEET 3.

l' f l f A j V5 Ms/ZM UNITED sTATEs PATENT oEErcE.

CHARLES H. FULTON, OF ST. LOUIS, MISSOURI, ASSIGNOR, BY MESNE ASSIGNMENTS, TO METALLURGICAL LABORATORIES, INCORPORATED, OF CHICAGO, ILLINOIS, A

CORPORATION OF ILLINOIS.

ELEOTRICAL DISTILLING APPARATUS.

Application filed December 7, 1916.

To all whom 'it may concern.'

Be it known that I, CHARLES H. FULTON,

a citizen of the United States, residing at St. Louis, Missouri, have invented a certain new and useful Improvement in Electrical Distilling Apparatus, of which the following is a full, clear, and exact description, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to an apparatus for electrically distilling ores and metal bearing materials.

In my pending application Serial No. 109,724, filed July 17, 1916, I have described a novel'method of electrically distilling zinc ore for the recovery of spelter or oXid, which method, briefly described, consists in forming pulverized ore, a reducing agent and a suitable binder into ore briquets of the character described in my U. S. Patent No. 1,198,680, dated August 8, 1916, interposing the briquets as a continuous, Xed resistor between electrodes in a closed retort furnace and passing through them an electric current of such strength as will cause the briquets to be heated lto a distilling temperature, and thereafter,- recovering the zinc Vapors of distillation in the form of spelter or zinc oXid.

One object of my present invention is to provide an efficient apparatus for practisin the method described in my pending application above referred to.

Another object is to provide an apparatus for electrically distilling ore and other metal-bearing materials and recovering the metal content of same, which is so constructed that the charge and the residue can be handled more conveniently and at a lower labor cost than is possible with any distilling apparatus now in general use, thereby materially reducing the cost per ton of distilling ores and metal-bearing materials.

Another object is to provide an apparatus of the character referred to that can be operated practically continuously. And still another object is to provide an electric furnace for distilling ores and metal-bearing materials which is so constructed that the heat losses are reduced to Specication of Letters Patent.

Patented Oct. 9, 1917.

Serial No. 135,631.

a minimum and the distillation can be accurately controlled. Other objects and desirable features of my invention will bc' hereinafter pointed out.

My complete apparatus consists of an electric furnace provided with a closed chamber or retort and constructed in such a manner that ore or metal-bearing material in the form of ore electrodes or briquets can be heated in said chamber to a distilling temperature by passing an electric current through said ore electrodes or briquets, and a condenser arranged in such a manner that the product 0f thedistillation of the charge will pass from the closed chamber of the furnace into the condenser. Means is pro* vided for accurately controlling or regulating the temperature of the condenser, and if desired, said means can also be utilized to heat the base of the furnace. The particu lar construction of the furnace and condenser is immaterial, so far as my broad idea is concerned, and the particular arrangement of the condenser with relation to the furnace is also immaterial, so long as said elements are arranged in close proX- imity to each other. In the apparatus herein shown, which is intended to be used for electrically distilling zinc ores or material containing zinc in the metallic form, the complete apparatus in its simplest form comprises a condenser, a pair of retort bases, on either of which the charge in the form of briquets or ore electrodes can be arranged and a. hollow member that is adapted to be set on the base containing the charge, so as to form a retort or closed distilling chamber. While said charge is being distilled another charge is set up on the second retort base, and at thecompletion of the distilling operation said hollow member or retort is removed by a crane or other suitable device from the base on which it rests, and thereafter arranged in operative position on the second retort base on which the second charge has been set up. If it is desired to have the apparatus operate practically continuously, the complete apparatus will coinprise a condenser, a plurality of retorts 0l' hollow members and one more retort base than there are retorts, thus giving one base on which the electrodes or briquets can be quenched at the completion of the distilling operation and a new charge set up while the other charges are being distilled in the retorts. The condenser also preferably comprises a base that is combined with the retort bases, and said various bases are provided with ducts or passageways through which a heating medium can be circulated, so as to heat the condenser and the retort bases, or a cooling medium can be supplied to the condenser, so as to maintain the condensing surfaces of the condenser at the proper temperature.

It is essential to the successful operation of my apparatus that the ore or metal-bearing material bein the form of briquets or ore electrodes having certain characteristics at the time the charge is introduced into the retort in which it is distilled, one of said characteristics being that the briquets or ore electrodes will not break down or disintegrate in the course of the distilling operation, and another characteristic being that said briquets or ore electrodes will preserve their form and volume and will not shrink away from the conductors or electrodes of the furnace, thus causing arcs, due to imperfect contact. In distilling zinc ore the briquets or ore electrodes are formed in the manner described in my patent previously referred to, for'example, from hard coal tar pitch, or any other suitable binder in a finely ground condition, which is mixed with pulverized ore and coke until a uniform mixture of the three is obtained. The mixture is then heated to the melting point of the pitch, which melts and softens in place and thoroughly coats each particle of ore and coke. The mixture is then formed into ore electrodes or briquets of any desired shape, preferably cylindrical shape, in suitable molds in which they are subjected to a high pressure, preferably upward from 500 pounds to the square inch, to solidify the mixture and form it into as irm and compact a mass as possible. nstead of forming the ore electrodes or briquets in the manner above described, they can be formed byv dry mixing ore and coke and then adding molten pitch and'mixing prior to briqueting. Thereafter, the ore electrodes or briquets are preheated or dried, so as to drive off the volatile hydrocarbons of the binder, and thus produce a briquet or ore electrode that consists 'of a large number of ore particles embedded in a coke matrix,

which briquet or electrode will maintain-y both'its form and volume during the distilling operation and serve as proper reA sister-conductor of the electric current between the electrodes of the electric furnace in which the distilling operation is carried on.'

Figure l of the drawings .is a vertical sectional view of an apparatus constructed in accordance with my invention and provided with two retort bases and a single retort.

Fig. 2 is a horizontal sectional View, taken on the line 2 2 of Fig, l. I

Fig. 3 is a vertical cross-sectional view,- taken on the line 3 3 of Fig. 2.

Fig. l is an enlarged vertical sectional view of the furnace consisting of the retort and the retort base.

Figs. 5, 6 and 7 are horizontal sectional views, taken on the lines 5 5, 6 6 and 7 7, respectively, of Fig. 4f.

Fig. 8 is an enlarged perspective view of one section of the supporting structure that carries the conductors or electrodes on which the charge rests during the distilling operation.

Fig. 9 is an enlarged vertical sectional. view of the con denser.

Fig. 10 is a horizontal sectional view, taken on the line 10-10 of Fig. 9.

Fig. 11 is a development of the tubular member that forms the outer shell of dthe condenser, illustrating the arrangernentY of the baffles arranged on the inner 'side of said member; and

Fig. 12' is a top plan view of an apparatus constructed in accordance with my invention V and provided with two retorts and three re tort bases. l

Referring to Fig. 1 of the drawings, which illustrates one form of my invention', A designates a retort or a vertically-dis# posed hollow member that is arranged on a base B, so as to form the distilling chamber C of an electric furnace, said retort A being removably mounted on the base B, so that it can be lifted therefrom byia crane or othervsuitable dev-ice (not shown) and arranged in operative position on a second retort base B." Acondenser D, which is provided with a base E, is arranged between the retort bases B and B, said retort bases and condenser base being built up of reranged symmetrically around the condenser D and two retorts A and A', as shown 'in Fig. 12, so as ,to enable the yapparatusto be operated practically continuously, :1s-*here-l inafter described, the particular number ofretorts and retort bases being immaterial,

so long as there is' one more retort' base than there are retorts.

The retort A can be' constructed in various ways without depurtingv lfrom the-spirit of my invention, but lf prefertoconstruct" it from a steel shell Il linedivitfi refractory and non-conducting 'materialH2',1

and having its ici/ver end portion l'Il `contracted slightly, as shown in Fig. 4, vso as to retain the material 2 in theshell when the retort is being transferred from one retort base to the other. The lower endl of said retort is open, and at the upper end of the retort is a discharge opening 3 that is normally closed by a cover 4 formed of refractory material. The retort base B is provided with a perforated supporting structure F of the form shown in Fig. 7, on which conductors or electrodes 5 and 6 are mounted, said supporting structure F being preferably composed of a plurality of sections 7 of refractory material, so as to enable it to be molded from fire clay and handled conveniently when the furnace is constructed to receive ore electrodes or briquets of large size. The supporting structure F is so formed that numerous holes, spaces or passageways are provided through same and at the periphery of same through which the products of the distillation can escape from the distilling chamber C, and said supporting structure is in turn carried by a checkerwork formed from fire lbrick 8 that rest upon an inclined plate 9 which forms the top wall of -an annular passageway 10 in the retort base B through which a heating medium can be caused to circulate, as hereinafter more fully described. If the furnace is designedfor use with a three-phase alternating current connection of the Y type, the electrode or conductor 6 will consist of a three-arm neutral point electrode or conductor, and the conductors 5 will consist of substantially segmental-shaped electrodes that are arranged between the arms of the neutral point conductor 6, the conductors or electrodes 5 and 6 being formed from graphite, or an orecoke-pitch mixture, substantially the same as in an ore briquet. The supporting structure F is provided with raised portions on which said conductors 5 and 6 rest, and each section 7 of said supporting structure is provided with an opening 7a that extends clear through same, so as to permit the products of the distillation to escape freely from the distilling chamber. The-graphite conductors that supply electric current to the conductors 5 and 6 are led into the retort base B through openings therein, and each of said electrodes is connected at its inner end to a plug 11 of conducting material that is arranged in an opening 12 in the supporting structure F, the upper ends of Said conducting plugs l1 contacting with the conductors 5 that rest upon the supporting structure F.

The ore or metal-bearing material to be distilled is rst formed into briquets or ore electrodes W', as previously described, and said ore4 electrodes are then arranged in an upright osition on the conductors 5 and 6 of the urnace, said briquets or ore electrodes being either in the form of-comparatively short, cylindrical-shaped objects, a number of which can be superimposed one upon the other to form a vertical column, or each ore electrode can consist of a comparatively long object. In practice I prefer to form each ore electrode as a single unit of approximately twelve inches in diameter and siX feet in height, weighing approximately 550 to 600 pounds, as ore electrodes of this character can be handled conveniently when setting up the charge and in removing the residue from the base of the furnace. In'setting up a charge in a furnace of the design herein illustrated twelve ore electrodes W are arranged in siX pairs on the conductors 5 and 6, the neutral point conductor 6 supporting six ore electrodes, and

each of the conductors 5 supporting two ore electrodes. Thereafter, conductors 13 of the form shown in Fig. 5 are arranged in engagement with the upper ends of the ore electrodes W, so as to electrically connect the tops of two adjacent pairs of ore electrodes. After the ore electrodes W have been set up and connected together in the manner described, the retort A is arranged in operative position on the base B over said electrodes. When the current is turned on the current conveyed to the pair of ore electrodes W resting on the conductor 5 at the left hand side of Fig. 6 will pass upwardly through said ore electrodes to the conductor 13 at the upper ends of same which electrically connects said ore electrodes to the ore electrodes supported by the lower left hand arm of the conductor 6, thence downwardly through the ore electrodes resting on said arm to the neutral point at the center of the conductor 6. The passage of the current for the other pairs of ore electrodes is similarly all convergent on the neutral point of the conductor 6 which gives the common Y connection of the alternating three-phase current. It will, of course, be understood that it is immaterial, so far as my invention is concerned, how the electriccurrent is supplied to the'ore electrodes, so long as the electrical resistance of the ore electrodes is such as to cause a suicient heat development within the charge itself to practically completely distil the zinc therefrom. By varying the amount of current sent through the ore electrodes W the speed of distillation may be kept under perfect control and the rate of distillation be varied at will. The current is preferably supplied to the furnace througha transformer so designed as to supply current at di'erent voltages. If the current is too great or too small at any given voltage, the voltage of the transformer may be decreased or increased until the proper flow of current is obtained. In starting a new furnace the amount of current passed through the ore electrodes is prefertorts andr-t ablyv atlrst. relatively small, so lthat the-4I walls 'of the retort A- will beheated rather' said heated passageway through a duct 1Ql into the condenser,`as indicated by the arrows in Fig. 1', the ducts 14 and 16 being provided` withV suitable controlling valves 14 andlG". 'Iheheatedrpassageway 15 in the base of the condenser is provided with aclean-out opening 17 that is normally closedl by a cover 17, and the bottom of said passageway slopes downwardly to a' lspelter takeloif 18 that is normally closed by a cover 18,as shown in F ig. 3.' In the condenser `D the zinc vapor 'is condensed asV liquid metal and the carbon monoxid escapes from a suitable ,vent or vents in the con-l denser andburns.

.If the a paratus is provided with two ref retort bases, as shown in Fig. 12, the distilling operation in one retort 1s startedfsome time after the distilling operation in the other retort is commenced. In practice I preferto start the distilling operation; in one retort about four hours after distillation has started in the other retort. Shortly-thereafter. a charge is also placed on the third retort basev and about eight hours' after the first retort.. that was started hasbeen in operation, the distillation.of its charge will'be finished. Said retort'isthen v vliftedaby a -crane or,Y other suitable device froml its ibase, .andi while white hot, 'is down over the charge, on the third retort base which now starts-distillation. The or'e charge on 'thefbase from which the retort was-removeddssquenched with a water spray and removed 'from :said 'ibase and al newy chargeset up on said base Assoon astheA 5b 1charge-in thefsecondV retortis distilled (about 5'5- are alwaystwo, charges in' process'of1 distillation and; practica-ily a continuous `flow of* zinc vapor :and carbon monoxid `into .the v eight hours ater it has started), said retort is-li-f-tedoii:I itsbase and set overthe charge f, that has been previously. set up: on-theirstbase. 'It willthusbe-seen thtin an a` pa-r ratus ofthe.' form4 shown in Fig. `12 t ere condenseris-obtainedh i fllhepro'dllct .eilt-he distillation oftheore Chrgefeomistsc-:nlgout equal volumes: of

'I vapor. r In 'the' eenden nuagesv about 870' C. when the aseous mixture con-v` sists of equal volumes o vzinc vapora'nd car bonn-monoxid gas'. Said zinc 'gas'musnhow-f ever, not be cooled to below the meltingI point of zinc, which is '419 C., 'for *other` wise, it will not condense to liquid metal,

but, on the contrary, will be converted into der. The cooling range, therefore', lies 'be`y tween 870 C'. and 419 C., but for practical' -a nely divided solid known as blue powfv4 purposes, in order to vobtain a nolten"r`11`e'tal from the condenser D, the cooling'lwillA carried to only 550 C. or 600 C.

It follows, therefore, that the surfac'es'in the condenser upon which the`metal'is, to be condensed as liquid spelter must alwayjsfhave the temperature within the'limits'nientiore'd;v It` is also best that the cooling o'fthe'fgass j from the temperature atwhich they en'ter' gradual, rather than rapid, 'and' therefore; i the condenser surfacesshould' presenta range oftemperatureirom about 870 7G.' to;

550? C: Any condenser whq'se condens'ingA surfaces` are at abol'lftl` the temperature l above mentioned will 'lose heat by radiation into' the atmosphere, the 'amount4 of heat'- which' is lost -into the atmosphere depending upon the surface of the lcondenser exposed l'tofthe? atmosphere andthe heat' conduf'ztivity ofthe'l material of 'which the' condenser is built?" Commonly speaking, the condensation Eoff zinc vaportimplies dissipation` of heat. Inl round numbers the condensation xof? one pound of zinc vapor from la"mix 't1`1're of equal volumesl of zine vapor andcarbi" monoxidr gas liberates 1,051 BST. U." The amount of heat.- liberated in any given con- I denser is therefore a 'function of-the amount' of zinc -condensed'. 'Now, iii-the'zincgconl-fvv densedbe relatively smalland the radiationu from the condenser 'be large, itfisf evident that in order to obtain vthe proper tern'jel'm;-`

ture 'within' theA condenser it" is necessaryto' supplyv additional heat tothe 'condenserL-- If,"

on'the other ll1:'11`1'd ,"the amountof 'zinc coni"l densedbe `relatively large, the Vheat liberated' by its condensation may be so 'great'tlat ordinary radiation may not be 'su'ici'ent"tl maintain the surfacesin theiiitgeriorgiofthe'; lcondenser at the proper temperature; tthi'ls' `makingit necessary to oolitheconderfs'er."

`Another important considerationin theV CCleiE of t-c'ondensationmare` necessary', f That is,

condensation of zinc vapor to'lijguid rectal I if there be provided in a space a large number of points or nuclei upon which the vapor has condensed into liquid, these small particles of liquid already formed facilitate the further condensation of the vapor. Some surface must be provided for this socalled nuclei to gather upon, and if a construction is obtained consisting of surfaces against which the mass of vapor is constantly swept, condensation is greatly facilitated.

In order that the condensing surfaces of the condenser may be maintained at a tenipcrature ranging from 870 C. to 550o C., 1 have provided the apparatus with means for enabling the condenser to be either` heated or cooled, and in order to facilitate the condensation of the vapor, I have constructed the condenser in such a manner that the zinc vapor will have a certain definite Velocity of flow over surfaces upon which zinc nuclei have been formed. 1n the form of my invention herein shown the .condenser D consists of a tubular-shaped member 19 closed at its upper end and arranged in an upright position on the condenser base E, a tubular-shaped member 20 arranged inside of the member 19 and spaced away from the side walls of same, so as to form a passageway, and a tubular-shaped member 21 arranged inside of the member 2O and spaced away therefrom, se as to form a passageway, as shown in Fig. 9, the members 19, 20 and 21 being preferably formed from refractory material and being of eylindrical shape in cross section. The member 21 is closed at its upper end, and the lower end of said member communicates with the duct 16 in the condenser base, so that the products of the distillation can circulate upwardly through the member 21 to a duct or passageway 22 that leads from the upper .end of the member 21 to an annular passageway Y between the members 19 and 20 that contains bales 23 which are so arranged that they will serve as condensing surfaces over which a mass of zinc vapor constantly sweeps, when the condenser 1s in operation. Means is arranged inside of the member 21, so as to retard the passage of the `zinc vapor through said member, which means preferably consists of a plurality of horizontally-disposed bafl'les 24 of rectangular form that are arranged one above the other and spaced apart by short struts or uprights 25. The baliies 23 and the annular condensing passageway Y preferably consists of inclined vanes that extend spirally around the member 20 at an angle of approximately 90, and said vanes are so arranged that the zinc vapor w1ll follow a tortuous path after entering the condensing passageway Y. As shown in Fig. 11, two of the vanes 23 that extend downwardly from the upper end of the passageway Y terminate a short distance from the bottom of said passageway, and one of the two intermediate vanes 23 extends upwardly from the bottom of the passageway Y and terminates a short distance from the upper end of said passageway. The other of said intermediate vanes extends unbrokenly from the bottom to the top of said passageway, thus forming a partition which causes the zinc vapor to follow the path indicated by the arrows in Fig. 11. At the upper end of the condensing passageway Y are one or more ports 26, shown in dotted lines in Fig. 9, through which the carbon monoXid gas can escape, and at the lower end of said passageway are one or more ports 27 through which the spelter can be drawn out of the passageway.

The condensing surfaces of the condenser can be maintained at the proper temperature by supplying either a heating medium or a cooling medium to the annular flue or space between the two tubular-shaped members 20 and 21 of the condenser, the upper end of said flue communicating with the atmosphere through an opening 28 formed in the top of the condenser and the lower end of said flue communicating with a chamber 29 in the base E of the condenser to which heated air or cooled air is supplied. A checkerwork of lire brick 30 is preferably arranged in said annular flue, so as to absorb heat from the products of combustion or heated air that travels through said ilue, and thus heat the condensing surfaces of the condenser that are arranged on opposite sides of said flue. One convenient way of supplying heat to the chamber 29 is to form two combustion chambers G in the base E of the condenser, as shown in Fig. .2', at points below the passageways 15 through which the products of`the distillation pass in escaping from the retorts to the condenser, each of said combustion chambers consisting of a hollow space in the condenser base, provided in its end wall with a burner port 31 and equipped with baffles 32 arranged zig-zag, or in any other preferred manner.. Duets 33 lead from the combustion chambers G to the chamber 29 in the base of the condenser with which the lower end of the annular flue of the condenser communicates. The condenser base is also preferably provided with combustion chambers G that are connected by means of ducts 34 with the annular passageways 10 in the bases B and B of the retorts, so that the retort bases may be heated, thereby reducing the consumption of electrical energy when the retorts are in operation, and also facilitating th'e starting of the apparatus wlen it is irst put into operation. As shown in Fig. 2 of the drawings, each of the retort bases is provided with a return duct 34;@t that leads from the annular pasparatus ofthe type now in'general use.

sageway 10 into the duct 83 in `the conden'ser base @that leads to the chamber 29. The combustion 'chambersG in thebase and Ltheduc'ts that lead from said chambers to the annular flue of the condenser 'form a convenient'means for heatingthe condenser, and `when it is desiredlto cool the condenser, 'the combustion chambers can be connected up With a fan or other suitable device by which cool *air can be forced into the annular flue of the condenser.

` 'With l'an apparatus of the construction above described,l the 'necessary heat energy to distilthe charge isfdeveloped Within'the charge itself, thus cutting down heat losses to a minimum', the amountof energy that v'can be put into thecharge'can be varied at Will 'by changing the voltage of the electric current by means of a transformer, thusenabling the distillation to be perfectly controlled; and still v:another desirable feature of such an apparatus is, that the energy put into the charge lcan be so adjusted that the distillation period may be reduced to eight hours, or less, as against the 4twenty-'four lhours now customar in the ordinary distillation furnace. T e fact that the charge is introduced into the furnace inthe form 4of comparatively large briquets or'sol'id electrodes Which uretain their original 'form 'throughout the distilling operation and after said operation has been l completed, materially reduces the labor'cost of operating the apparatus; enables a practically complete 'distillation of the zinc to take place and insures the recovery of a greater percentage of zinc than is possible with zinc distillingrlaphe apparatus can be built in large sizes; it can be operated practically continuously and it is so constructed that the temperature of the condenser can be accurately lcontrolled. Having thusv described my invention, What I claim, and "desire to secure by 'Letters Patent, is: l

1. An apparatus for distilling ores vand 'metal'bearing materials, comprising a :retort lor chamber constructed to' receive a charge consisting of fine ore or metal-'bearing material and a suitable reducin agent iformed into'a compactm'ass that Wil retain its substantially originalform and volume When subjected to a distillation temperature, means for causing an electric `current -to 'pass directly through said mass so asto heat same to N"a ldistillation temperature, and means for thereafter -condensing the products lof the distillation.

2. Anfelec'tric distilling furnace, comprising a distilling chamber, and anielectricallyoperated heating meansin said chamber conslsting vof a molded structure of substantially cellular formation Whose cells con- 'tainineta'l 'that is to be distilled. l A

"3. An apparatus for distilling lres and metal-bearing materials, comprising an electric furnace composed o'f "a retort and electric conductors between lwhich electrodes lcontaining the substance to be distilled are tric furnace composed of a retort and electric 'conductors between which electrodes containing the substance to be distilled are adapted to be arranged so as to form a continuous resistor, said furnace being so constructed that said electrodes can be positioned lon the eonductors that supply cu-rrent to same and thereafter arranged vin operative position in the retort, a condenser, and means l'whereby 'the products of the distillation can pass from said'retort into said condensr. v i

5. An 'apparatus for distilling ores and Ametal-bearing materials, com rislng an elect'ric distilling furnace, a con'I enser combined with said furnace in such a manner that the -productsY of the distillation can be ad- 'mitted from the furnace 'to said condenser, and means whereby a heating medium can be supplied to the condenser to control the temperature of same and also to said furnace to prleliminarily heat the furnace priorto the distillingv operation orto diminish the electricalenergy required in the distillingoperation. v

6. lAn apparatus for distilling ores and metal-bearinginaterials, comprising an electric furnace, a condenser, a passageway through `vvhich the products of the distillationtravel'from the furnace to said condenser, =an `air heating means,l and ducts leading 'from saidair heating means to said condenser and .furnace to heat same.`

A11 apparatus for distilling ores and metal-'bearing materials, comprising a base or 'supporting structure, an electric furnace, anda condenser carried by said structure, means for'admittin the products lof the distillation 'from sai furnace Vto said condenser, ,and ducts or ,'passageways vin said supporting 'structure through fwhich a mecan fbe supplied 'to modify the temperature'of said furnace and condenser.

y 8. An apparatus for distilling oresand metaLbearing materials, comprisingl a base or 4snpplnjtmgfstructure, an electric furnace and, a-condenser carried by said structure, means for admittngfthe products of the distlllatlon from said furnace to said condenser, av 'combustion chamber in said supportstructure, and ducts or passageways vfrom'said combustion chamber to said furnace andcondenser.

9. An apparatus for distilling ores and metal-bearing materials, comprising a base or supporting structure, an electric furnace comprising a retort that is removably mounted on said supporting structure, a condenser on said supporting structure, and a passageway through which the products of the distillation can pass from said retort to said condenser.

10. An apparatus for distilling ores and metal-bearing materials, comprising a condenser, a plurality of retort bases, a retort constructed in such a manner that it can be removably mounted on either of said retort bases, means whereby a charge supported by either of said bases can be electrically distilled when said retort is in operative position over said charge, and means whereby the productsl of the distillation can pass from the retort into said condenser.

11. An apparatus for distilling ores and metal-bearing materials, comprising a plurality of electric furnaces, each of which comprises a base and a retort removably mounted on said base, aseparate retort base on which one of said retorts can be arranged., a condenser,'and passageways leadl metal-bearing materials, comprising a plurality of retort bases and a condenser base combined as a single structure, a condenser on said condenser base, a retort constructed in such a manner that it can be arranged in operative position on either of said retort bases, combustion chambers in said structure, and ducts or passageways leading from said combustion chambers to said bases.

13. An electric distilling furnace, comprising a distilling chamber, and an electrode in said chamber that forms part of the electric circuit used to operate the furnace, said electrode consisting of a vmolded member'or a plurality of members that contain metal to be distilled and arranged in such a manner that ample space is provided between the exterior of the conductor and the walls of the distilling chamber to permit the free escape of the vapors evolved in the distilling operation.

14. An apparatus for distilling ores and metal-bearing materials,- comprising an electric distilling furnace and a condenser conrality of retort bases and a condenser basel combined as a single unit, means on each of said retort bases for supporting a charge of ore or metal-bearing material, a retort constructed in'such a manner that it can be arranged on either of said retort bases over a charge thereon, means for electrically distilling the charge inclosed by the retort, a condenser on' the condenser base provided with a vertical flue for heating the condensing surfaces of the condenser, means whereby either a heating medium or a cooling medium can be supplied to the flue of the condenser, and `passageways leading from said retort bases to the condenser for supplying the products of the distillation to the condenser.

16. An electric distilling furnace, com'- prising a retort or distilling chamber, electric conductors, andv a continuous resistor arranged in engagement with said conductors and consistingof fine ore or metal-bearing material and a suitable reducing agent formed into a compact mass that will retain substantially its original form and volume when subjected to distillation temperatures.

17. An electric distilling' furnace, comprising a'retort or distilling chamber, spaced electrodes arranged adjacent the opposite ends of said chamber, and a continuous resistor interposed between said electrodes and composed of a plurality of electrodes containing the substance to be distilled and constructed in such a manner that they will retain substantially their original form and volume when subjected to distillation temperatures.

18. An electric distilling furnace, comprising a retort or distilling chamber, a plurality of electric conductors arranged adjacent the lower end of said 'chamber and adapted to support a plurality of verticallydisposed electrodes that contain the substance to be distilled and which constitute a continuous resistor, and means for electrically connecting the upper ends of said electrodes together.

19'. An electric distilling furnace, comprising a retort, means for supporting in said retort and electrically connecting together a plurality o'f electrodes that constitute a continuous resistor, and means whereby'the products of the distillation can escape from said retort.

20. An electric distilling' furnace, comprising a retort, electrodes for supporting the 'charge that is to be distilled, and a supporting means for said electrodes constructed in such amanner that the products of the distillation can escape freely from thelower end of the retort.

' 21. An electric distilling furnace, com- '.end. I

Ysaid retortjand containing the substance to fbegdiilled, electric conductors on which 'said .el ectrocles vrest, and a perforated suppcrting`--structure at the lower end .of said rtcrt yfor supporting said electric lconduc- `.tor,s l

H22'. .electricdistilling furnace, complj-sing-l-alchamber providedwith an open lcwelgenmand an 'electric conducting means 10 arranged, .adjacent the lower end.ofsaid chamber orsupporting the charge to be distilled, s aid chamber and said means being, so, arrangedl that one can be moved .with relation 1to the other s0 asto permit the .l5 phaageto beset up or removed. A

1 -23,An electricvdistilling furnace, cmprising a base or supporting structure, means-onsaid structure `for supporting the chplgetobe distilled, and ,aretort or chamhaving an open lowerA end that is adapt- 'jg 24;, electric' distilling,\furnace, coma base-or supporting structure, elec- .tricgconductorspn said; structure on which fthe. charge, consisting of electrodes contain- :ingthe substance to' be distilled, can be argranged in; an upright position, `and a hollow member or chamber constructed in such a 3 0 manner that it can be .mounted on said ,structure over the charge prior to the disoperation andremoved therefrom at 1tlie completion of the distilling operation.

v 2@ An electric d istilling furnace, coml3K5 .prisinga base o Vsupporting structure, a

' removableretcrt mountedy nn said structure, means carried by said structure for supplyingelectric current toa charge in said retort, and ac ductgor passageway in said t4,0 fstiucture through which the products of fthe distillation canlescape said retort. Yelectric distillingfurnace, com p'rylslnga `bayseor supporting structure, and a removable retort. on said` structure composed-olf ametal shell provided with aflining -jo refractgry and. non-conducting material, the lower endportion ofsaid shell being ccntractedso as..to hold said lining inthe .shellwhenitheretortis removed from said otmsfucture A g. Artfele'ctric, distilling l f urnace, comprislngv a base, aretort removably mounted 911 :aid base and, a., trasforma-v Supporting structure carried by said-base. for sustainn ing-,electricconductors onwhich the charge .dlilliil fthe, dSilDg operation.

128i eectricldistilling furnace, comprising@ basa, apassageway in said base y,i`15191-1'gl1,which a heating medium can cir- 'GiGQll-,ltaland a retortremevably. mounted on said base and providedv with an open lower amasar 29. An electric distill-ng furnace, comprising a base, a hollow member open at its lower end and so constructed that it can be mounted on saidy base in an upright'position so as to. form a retort, a supporting structure on said base for sustaining electric conductors on which the chargerests during the distilling cperation, electrical supply conductors in said base, and plugs in said supporting structure that electrically connect said supply conductors with the conductors onfwhich the charge rests.

30,- An-electric distilling furnace, com,- prising 'abase provided with a chamber to which a heating medium can be supplied, an inclined member o n said base that forms .the

top of said chamber, a perforated supportsubjected to a distilling temperature,y and means for causing a currentl of electricity topass through said resistor.

32. An electric distilling furnace, comprising spaced-conductors, a continuous rcsistor interposed between said. conductors and consisting of fine orel or metal-bearing material formed in to a compact mass that will retain substantially itsv originaly form andl volume when subjected to adistilling temperature, and-ia retort cr chamber for inclosing said resistor.

'33. An electric'distilling furnace, comprising a distill-ing chamberfelectricalcon- 31. An electric distilling furnace, comductors that -form part of the circuitused to operate the furnace, and a molded structure yin said chamber that establi's-hesvv electrical Conil@@tivai between Said.- Conductqrs, and which is adaptedtobeheated to a dlstilling temperature by' the'- electric 'current which flows through 'the cir'cuit, saidmolded structure having combined therewith the substance to beydistilled,

,341. .electric distilling furnace whose.

heating means consists o f'a resistor larranged in the electric circuit `used-tooperate the furnace and havingv cqinbincd therewith metal that is to be distilled, sald'res1stor being so constructed thatfit will retain its substantially originali-form and. volume after'the metal has been distilledtherefrom.

FULTON. j 

